Method and apparatus for controlling the throat height of batch fabricated thin film magnetic transducers
CA 1249075 A · Owner: International Business Machines Corporation · Inventors: Church, Mark A.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method for determining the position of a lapped edge of a substrate during lapping of a row of thin film magnetic transducer elements. First and second electrical lapping guide structures are formed on each side of the row of transducer elements. The lapping guide structures include a series of switching junctions each switching, junction paralleled by a resistor. A lapping resistor which provides a change in resistance proportional to the lapping of the row is measured and compared with the position of the lapping plane as determined from each switching junction change of state. Calibration of the resistor versus lapping plane position is effected to permit an accurate determination of …
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Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Granted January 17, 1989. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended January 17, 2006.
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Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.